28 

 LIMNEA ATTENUATA, Say. 



Plate 9. — Figs. 1 — 5. 



L. test elongata, tenuissima, diaphana, fragili, acuta: 

 anfractibus 7 planulatis: sutura impressa, obliqua: aper- 

 tura semicirculari; plica columellari impressa. 



SYNONYMS AND REFERENCES. 



LiMNEUS ATTENUATUS, Say. Disseminator, p. 244, Aug. 

 12th, 1829.— Mrs. Say's reprint, p. 23. 



DESCRIPTION. 



Shell very long and slender, with seven 

 slightly convex whirls, revolving obliquely: 

 suture rather deep: apex suddenly pointed: 

 aperture small and semicircular, sometimes 

 expanded: columellar plait well marked. The 

 young shell does not differ materially from the 

 adult. 



Color wood-brown. 



Geographical Distribution. Found by Say 

 in the ditches and ponds about the city of 

 Mexico. 



